This invention relates generally to captive panel hardware. More particularly, the present invention is concerned with a unitary, preferably non-metallic, captive panel screw.
In the prior art a plurality of captive panel devices have been proposed. Basically captive panel hardware is employed to provide various forms of spacers, bosses or anchors to which mechanical structure such as printed circuit boards, panels, tie downs or other terminals or accessories may be attached or secured. As will be appreciated by those skilled in the art, rapid installation of captive panel hardware during assembly, for example, of electro-mechanical components, may greatly reduce labor and tooling costs.
In the past a variety of captive screw structures have been proposed. For example, relevant prior art known to me comprises U.S. Pat. Nos. 3,571,904; 3,346,032; and 3,560,132. The foregoing patents relate to multi-component structures which are adapted to be captivated relative to a suitable orifice provided in a workpiece. However, captivation occurs in response to the assembly of a variety of usually coaxially interfitted parts which must be carefully assembled for successful installation.
Besides the obvious labor related cost inefficiencies of multi-component captive panel assemblies, the use of metallic parts generally results in the necessity of several operations to successfully install or manufacture the devices. For example, certain metal pieces must be flared during a secondary installation operation. During such operation damage often occurs at the hands of inexperienced assembly personnel. Also, the use of metallic components generally is disadvantageous in conjunction with the assembly of electrical or electronic apparatus. Moreover, the metallic colors of conventional captive panel hardware often clash aesthetically with the end product.